Spinning solution containing n-substituted amide, polymer, and cellulose acetate



United States Patent No Drawing. Filed Nov. 7, 1955, Ser. No. 545,521 4 Claims. (Cl. 260-47) This invention concerns an improved spinning solution, more particularly a spinning solution containing cellulose acetate and a polymeric material.

Cellulose acetate is commonly spun from a spinning solution in which the cellulose ester is dissolved in acetone. However, the cellulose acetate has little, if any, affinity for most wool dyes such as those containing acid groups. This property is often disadvantageous, since many of the wool dyes are easily applied and relatively cheap.

Cellulose acetate is an excellent fiber for blending with wool. However, due to the fact that acetate-wool blends cannot be satisfactorily union dyed, its use in such mixtures has been restricted. Dyeing of a material consisting of wool and cellulose acetate in the same dye bath has resulted very often in each of the components having a different color or in some instances in one of the components notbeing dyed. It was difficul-t to dye such blends, therefore, due to the necessity for using special dyeing techniques, such as dyeing the material in successive baths with the attend-ant possibility of still obtaining uneven dyeing.

Furthermore, it has not been possible to successfully finish fabrics containing cellulose acetate with conventional textile finishing agents which are applied to other fabrics such as cotton and viscose in order to improve such properties as hand, crease recovery and wrinkle resistance, and abrasion resistance. When formaldehydeeontaining finishes, for example, are applied to cellulose l acetate fabrics, they stay only on the surface of the acetate, giving a stiff, boardy fabric that has poor crease recovery and poor abrasion resistance.

Another characteristic of ordinary unmodified cellulose "acetate in wool blends i-s that it does not lend itself to fulling. The hand of fabrics made from wool is enhanced by the process of fulling, which is related in part to the ability of wool to shrink under certain conditions. Ordinarily when other fibers such as unmodified cellulose acetate and the like are blended with wool, only the wool can be fulled and the resultant fabrics do not have a wool-like or luxuriant hand. Such fabric blends are said to have a synthetic or non-wool-like hand, a property which is generally not considered to be desirable.

In addition, many synthetic fibers have a cold or unnatural feel due to low moistureregain or the inability of the fibers when dried to take up moisture. Consequently, it is desirable to have a relatively high moisture regain in order for fabrics to feel comfortable in contact with the skin. Moreover, fibers which have a high ,moisture regain do not tend to build up static charges; accordingly, they process much more easily than fibers with a lower moisture regain, and are also less prone to soil, etc. in actual use.

I have made the discovery that a spinning solution for preparing a modified cellulose acetate can be prepared which results in modified cellulose acetate fibers which have other improved properties over, cellulose acetate which has not been somodified.

One object of this invention is to provide a spinning solution resulting in an improved modified cellulose acetate fiber. Another objectof invention is to procan be union dyed when blended with wool and which ice vide modified cellulose acetate fibers having improved dyeing properties. A further object is to provide modified cellulose acetate fibers which, when blended with wool, give excellent union dyeings with wool dyes. An additional object is to provide a modified cellulose acetate fiber which, when blended with wool, can be fulled to give a fiabirc of luxuriant hand.

A further object is to provide modified cellulose acetate fibers which have a higher moisture regain than ordinary unmodified cellulose acetate fibers. Another object is to provide modified cellulose acetate fibers which exhibit improved processing characteristics and superior hand, both alone and in blends with other materials such as wool. A further object is to provide modified cellulose acetate fibers which have a higher abrasion resistance than ordinary unmodified cellulose acetate fibers. Another object is to provide modified cellulose acetate fibers which when made into fabrics alone and in blends with other materials such as wool can be finished using resin finishes to further improve the hand, wrinkle resistance and abrasion resistance of the fabrics.

The above objects of this invention are obtained by modifying acetone-soluble cellulose acetate with acetonescluble homopolymers and copolymers of N-alkylacrylamides and N-alkylmethacrylamides and with acetonesoluble copolymers polymerized from monomeric mixtures containing at least 65% of an N-alkylacrylamide or N-alkyhnethacrylamide. The 65-100% must be either an N-alkylacrylarnide, an N-alkylmethacrylarnide, a mixture of difierent N-alkyl-acrylamides, a mixture of different Naalkylmethacrylamides, or a mixture of an N-alkylacrylamide and an N-alkylmethacrylamide. Copolymers as used herein includes polymeric compositions prepared from monomeric mixtures containing two or more monomeric materials.

More particularly, the sole monomer or the monomers comprising the 65-100% of the monomeric mixture in the case of copolymers from which the polymers are prepared which are operative in my invention include water-soluble Naalkylacrylamides and N-alkylmethacrylamides with the exception of the N-butyl acrylamides and N-butylrnethacryl-amides which are only slightly watersoluble. The homopolymer modifiers should include acrylamides having the structure wherein R is hydrogen or an alkyl group containing from 1-4 carbon atoms, and R is an alkyl groupcontaining from 1-4 carbon atoms, and methacrylamides having the structure RI CHz=OCON OH; R wherein R may be hydrogen or an alkyl group containing from 1-4 carbon atoms, and wherein when R is hydrogen, R is an alkyl group containing 2-4 carbon atoms. When R is an alkyl group containing from l-4 carbon atoms, R is an alkyl group containing from 1-4 carbon atoms.

Copolymers of these acrylamides and methacrylamides which are valuable for use in this invention contain from 65l00% of the above-described amides. Suitable monomers for copolymerization with the amides are unsaturated compounds having the structure In order for modifiers to be operable in my invention, they must not only be soluble in acetone, but must also be compatible with cellulose acetate. Compatibility of 'ta'te, direct, wool and vat dyes.

the polymers of this invention with cellulose acetate is completely unexpected since it is generally known that most polymers are not compatible with one another.

The compounds which may constitute up to 35% of the monomeric mixture from which the copolymer is prepared may be such compounds as vinyl esters, vinyl halides, acrylic and methacrylic acid derivatives such as nitriles, amides and esters, maleic and fumaric acid derivatives such as nitriles, amides, esters, mixed ester-amides and maleic anhydride. Preferably, the -35% of the monomeric mixture is made up .of monomers which contain fewer than 20 carbon atoms.

The unsubstituted acrylamides, methacryl-amide, and N-methylme'thacrylamide homopolymers are insoluble in acetone and copolymers containing high concentrations thereof are not operable inmy invention. However, when such amides are oopolymerized with highly soluble acrylamides, cop'olymers containing relatively minor concentrations thereof are still soluble in acetone. In general, copolymers containing less than 15% of these particular amides are acetone-soluble and are compatible with cellulose acetate.

The homopolymer and copolymer modifiers of this invention can be prepared by homopolymerizing or copolymerizing the N-substituted acrylamides and N-suostituted methacrylamides by the usual methods, such as solution, emulsion, and bulk polymerizations, using free-radical peroxide type or other suitable catalysts. The polymer zations can also be polymerized by heat, ultraviolet light, etc. The modified cellulose acetate can be prepared by either dissolving separately or together the amide modifier and the cellulose acetate in acetone. If dissolved separately, the solutions are combined.

The resulting spinning solutions contain from 15 to 35% by weight of cellulose acetate plus modifier, and from 85 to 65% by weight of acetone. The preferred solution has from 20 to 30% by weight of cellulose acetate plus modifier, and from 80 to 70% by weight of acetone. Although, for reasons of economics, acetone is the preferred solvent for use in spinning cellulose acetate having an acetyl content of below 42%, and modified according to my invention, it is to be understood that other solvents such as dimethylformamide, dimethylacetamide, methylene chloride, methylene chloride-methanol mixtures, cyclohexanone, methyl ethyl ketone, acetonitrile, and the like can be used.

It is also to be understood that all conventional wetand dry-spinning techniques can be used in the preparation of the modified cellulose acetate fibers of my invention. When wet-spinning techniques are used, an acetone or other solvent solution of the modified polymer can be extruded into coagulating baths containing water, hexane, and the like. When dry-spinning methods are used, the usual variations in equipment and technique can be employed.

By cellulose acetate having an acetyl content below about 42%, as is used herein, I mean to describe a cellulose acetate that is acetone soluble under ordinary conditions.

The following examples will further illustrate this invention. It is to be understood, however, that the invention is not limited by the specific illustrations except to the extent defined in the appended claims.

Example I Fibers spun from a spinning solution comprising 65 parts of acetone, 29.8 parts of cellulose acetate having an acetyl content of 39%, and 5.2 parts by weight of poly- N-isopropylacrylamide showed excellent afiinity for ace- Acetate dyes which have poor gas fastness showed excellent gas fastness on these fibers.

Example 2 Fibers spun from a spinning solution comprising 70 parts of acetone, 27 parts of cellulose acetate having an acetyl content of 40%, and 3 parts by weight of poly-N, N-dimethylacrylamide showed excellent afiinity for acetate, direct, wool, and vat dyes. These fibers, which had a moisture regain of 8%, processed well on commercial spinning equipment and were made into a fabric which after dyeing had an excellent, wool-like hand.

Example 3 Fibers spun from a spinning solution comprising parts of acetone, 16 parts of cellulose acetate having an acetyl content of 41%, and 4 parts by weight of N-tertiary-butylacrylamide showed excellent affinity for direct, acetate, vat, and wool dyes.

Example 4 Fibers spun from a spinning solution comprising parts of acetone, 13.5 parts of cellulose acetate having an acetyl content of 38%, and 1.5 parts by weight of poly- N-methylacrylamide showed excellent afiinity for direct, acetate, vat, and wool dyes. Blends of this fiber with wool gave excellent union dyeings with such wool dyes as Brilliant Milling Blue B (Prototype No. 37), Fast Red S, cone. (Color Index 176), and Milling Orange G (Color Index 377).

Example 5 Fibers spun from a spinning solution comprising 75 parts of acetone, 20 parts of cellulose acetate having an acetyl content of 35%, and 5.0 parts by weight of poly- N,N-dimethylmethacrylamide showed excellent atfinity for direct, acetate, vat, and wool dyes. Samples of the fibers or fabric dyed with Eastman Blue BNN (Prototype 228) exhibited excellent gas fastness. Unmodified cellulose acetate showed very poor gas fastness when dyed with this same dye.

Example 6 Fibers spun from a spinning solution comprising 75 parts of acetone, 21.25 parts of cellulose acetate having an acetyl content below about 42%, and 3.75 parts by weight of an 80/20 N-ethylmethacrylamide/ methyl acrylate copolymer showed excellent atfinity for acetate, vat, and wool dyes.

Example 7 Fibers spun from a spinning solution comprising 75 parts of acetone, 22.5 parts of cellulose acetate having an acetyl content below about 42%, and 2.5 parts by weight of a /10 N-isopropylacrylamide/acrylonitrile copolymer showed good affinity for acetate, vat, and wool dyes.

Example 8 Fibers spun from a spinning solution comprising 75 parts of acetone, 21.25 parts of cellulose acetate having an acetyl content below about 42%, and 3.75 parts by weight of an 85/15 N,N-dimethylmethacrylamide/vinyl acetate copolymer showed good afi'inity for direct, acetate, vat, and wool dyes. A 50/50 blend of this fiber with viscose gave an excellent union dyeing with Dark Orange G (Color Index 478).

Example 9 Fibers spun from a spinning solution comprising 75 parts of acetone, 18.75 parts of cellulose acetate having an acetyl content below about 42%, and 6.25 parts by weight of poly-N-methyl-N-ethylmethacrylamide showed excellent affinity for direct, acetate, vat, and wool dyes.

Example 10 Fibers spun from a spinning solution comprising 75 parts of acetone, 21.25 parts of cellulose acetate having an acetyl content below about 42%, and 3.75 parts by weight of an 80/10/10 N,N-dimethylacrylamide/vinylidene chloride/methylmethacrylate copolymer showed excellent afiinity for direct, acetate, vat, and wool dyes.

Example 11 Fibers spun from a spinning solution comprising 74 parts of acetone, 22.1 parts of cellulose acetate having an acetyl content below about 42%, and 3.9 parts by weight of a 75/ 25 N,N-dimethylacrylamide/N-isopropylacrylamide copolymer showed excellent affinity for acetate, direct, wool, and vat dyes and gave excellent union dyeings with wool. Wool dyes which ordinarily have poor light fastness showed excellent light fastness on these fibers. Fabrics made from these fibers took up commercial textile-finishing agents to give materials having improved properties and an excellent hand.

Example 12 Fibers spun from a spinning solution comprising 75 parts of acetone, 22.5 parts of cellulose acetate having an acetyl content below about 42%, and 2.5 parts by weight of a 90/ 1 N,N-dimethylacrylamide/N-methylmethacrylamide copolymer showed excellent aflinity for acetate, direct, wool, and vat dyes and gave excellent union dyeings with wool.

Example 13 Fibers spun from a spinning solution comprising 75 parts of acetone, 20 parts of cellulose acetate having an acetyl content below about 42%, and parts by weight of a 70/20/10 N,Ndimethylacrylamide/N-tertiary-butylacrylamide/N-isopropylacrylamide terpolymer showed excellent affinity for direct, acetate, wool, and vat dyes and gave excellent union dyes with wool.

Example 14 Fibers spun from a spinning solution comprising 65 parts of acetone, 33.75 parts of cellulose acetate having an acetyl content below about 42%, and 1.75 parts by weight of a 99/1 N,N-dimethylacrylamide/acrylamide copolymer showed good affinity for acetate, vat, and wool dyes.

Example 15 Fibers spun from a spinning solution comprising 75 parts of acetone, 17.5 parts of cellulose acetate having an acetyl content below about 42%, and 7.5 parts by weight of an 85/15 N-isopropylacrylamide/N-methylmethacrylamide copolymer showed excellent affinity for direct, acetate, wool, and vat dyes and gave excellent union dyeings with wool.

7 Example 16 Fibers spun from a spinning solution comprising 70 parts of acetone, 24 parts of cellulose acetate having an acetyl content below'about 42%, and 6 parts by weight of at 70/20/10 N,N-dimethylacrylamide/N-isopropylacrylamide/maleic anhydride terpolymer showed excellent affinity for direct, acetate, wool, and vat dyes.

Example 17 Fibers spun from a spinning solution comprising 80 parts of acetone, 16 parts of cellulose acetate having an acetyl content below about 42%, and 4 parts by weight of a 70/20/10 N,N-dimethylacrylamide/N-isopropylacrylarnide/diethyl fumarate terpolymer showed excellent aflinity for direct, acetate, wool, and vat dyes.

Example 18 Fibers spun from a spinning solution comprising 75 parts of acetone, 20 parts of cellulose acetate having an acetyl content below about 42%, and 5 parts by weight of a 70/20/10 N,N-dimethylacrylamide/N-isopropylacrylamide/vinyl acetate terpolymer showed excellent affinity for direct, acetate, wool, and vat dyes.

Example 19 Fibers spun from a spinning solution comprising 75 parts of acetone, 20 parts of cellulose acetate having an acetyl content below about 42%, and 5 parts by weight of a 65/35 N,N-dimethylacrylamide/methyl acrylate copolymer showed excellent aflinity for direct, acetate, wool, and vat dyes.

6 Example 20 Fibers spun from a spinning solution comprising 75 parts of acetone, 21.25 parts of cellulose acetate having an acetyl content below about 42%, and 3.75 parts by weight of a 75/15/5/5 N,N-dimethylacrylamide/N-isopropylacrylamidc/vinylidene chloride/vinyl acetate copolymer showed excellent afiinity for direct, acetate, wool, and vat dyes.

. Example 21 Fibers spun from a spinning solution comprising parts of acetone, 13.05 parts of cellulose acetate having an acetyl content below about 42%, and 1.95 parts by weight of a 10 N,N-dimethylacrylamide/methacry1- amide copolymer showed good affinity for acetate, vat, and wool dyes. I 1

Example 22 Fibers spun from a spinning solution comprising 75 parts of acetone, 20 parts of cellulose acetate having an acetyl content below about 42%, and 5 parts by weight of a 75/ 15/ 10 N,N-dimethylacrylamide/N-isopropylacrylamide/fumaronitrile terpolymer showed excellent afiinity for direct, acetate, wool, and vat dyes.

Example 23 Fibers spun from a spinning solutioncomprising 75 parts of acetone, 20 parts of cellulose acetate having an acetyl content below about 42%, and.5 parts, by weight of a 75/ 15/ 10 N,N-dimethylacrylamide/N-isopropylacrylamid'e/N,N,N,N' tetramethylfumaramide terpolymer showed excellent affinity for direct, acetate, wool, and vat dyes.

Example 24 Fibers spun from a spinning solution comprising 75 parts of acetone, 20 parts of cellulose acetate having an acetyl content below about 42%, and 5 parts by weight of a 75/ 15/ 10 N,N-dimethylacrylamide/N-isopropylacrylamide/N-methyl maleamate terpolymer showediexcellent affinity for direct, acetate, wool, and vat dyes.

' Example 25 Fibers spun from a spinning solution containing 74 parts of cyclohexanone, 22.1 parts of cellulose acetatehaving an acetyl content below about 42%, and 3.9 parts of a 75/25 N,N-dimethylacrylamide/N-isopropylacrylamide copolymer, which is acetone soluble, showed excellent affinity for acetate, direct, wool, and vat dyes and gave excellent union dyeings with W001. W001 dyes which ordinarily have poor light fastness showed excellent light fastness on these fibers. Fabrics made from these fibers took up commercial textile finishing agents to give materials having improved properties and an excellent hand.

Example 27 Fibers spun from a spinning solution containing 74 parts of methyl ethyl ketone, 22.1 parts of cellulose acetate having an acetyl content below about 42%, and 3.9 parts of a 75/25 N,N-dimethylacrylamide/N-isopropylacrylarnide copolymer, which is acetone soluble, showed excellent aflinity for acetate, direct, wool, and vat dyes and gave excellent union dyeings with W001. W001 dyes which ordinarily have poor light fastness showed excellent light fastness on these fibers. Fabrics made from these fibers took up commercial textile finishing agents to give materials having improved properties and an excellent hand.

Example 28 Fibers were spun from a spinning solution comprising 74 parts of acetone, 22.1 parts of cellulose acetate having an acetyl content below about 42%, and 3.9 parts of a 75/25 N,N-dimethylacrylamide/N-isopropylacrylamide copolymer by extruding the solution through a spinneret into a coagulating bath containing water. The resultant fibers showed excellent afiinity for acetate, direct, wool, and vat dyes and gave excellent union dyeings with wool.

Example 29 Fibers were spun from a spinning solution comprising 74 parts of acetone, 22.] parts of cellulose acetate having an acetyl content below about 42%, and 3.9 parts of a 75/25 N,N-dimethylacrylamide/N-isoprpylacryl amide copolymer by extruding the solution through a spinneret into a coagulating bath containing water. The resultant fibers showed excellent affinity for acetate, direct, wool, and vat dyes and gave excellent union dyeings with wool.

Example 30 Fibers were spun from a spinning solution comprising 74 parts of dimethylformamide, 22.1 parts of cellulose acetate having an acetyl content below about 42%, and 3.9 parts of a 75/25 N,N-dimethylacrylamide/N-isopropylacrylamide copolymer by extruding the solution through a spinneret into a coagulating bath containing water and isopropanol. The resultant fibers showed excellent affinity for acetate, direct, wool, and vat dyes and gave excellent union dyeings with wool.

Cloth manufactured from fibers manufactured according to this invention possesses the excellent properties found in the fabrics made from cellulose acetate fibers. Blended with natural fibers such as wool, the resulting fabric combines the advantages of both materials, for instance, combining the high elasticity of the natural fiber with the high ductility of the cellulose acetate. As a result of this invention, the possible fiber combinations r' are great in number and have widespread utility particularly in the apparel field.

This application is a continuation-in-part of US application Serial No. 368,807, filed July 17, 1953.

Parts and percentages as used herein are intended to be by weight.

I claim:

1. A spinning solution containing 85-65% acetone, 15-35% by weight of a mixture comprising 70-95% of a cellulose acetate having an acetyl content of 35-41%, and 30-5% of an acetone soluble polymer selected from the class consisting of homopolymers of N,N-dimethylacrylamide and copolymers of N,N-dimethylacrylamide with at least one unsaturated compound having the grouping in which at least of the monomeric mixture from which the copolymer is prepared is N,N-dimethylacrylamide, in which the compounds having the grouping are selected from the class consisting of vinyl esters, vinylidene chloride, maleic and fumaric esters, maleic and fumaric amides, maleic and fumaric nitriles, mixed esteramides of fumaric and maleic acids, and maleic anhydride, acrylic and methacrylic amides and nitriles, which class is made up of monomers which contain fewer than 20 carbon atoms.

2. A spinning solution containing from 85-65% acetone and 15-35% of a mixture containing -95% of a cellulose acetate having an acetyl content of 35-41% and 30-5% of an acetone-soluble copolymer prepared by polymerizing a monomeric mixture containing 90% N,N-dimethylacrylamide and 10% methyl methacrylamide.

3. A spinning solution containing from 85-65% acetone and 15-35% of a mixture containing 70-95% of a cellulose acetate having an acetyl content of 35-41% and 30-5 of an acetone-soluble copolymer prepared by polymerizing a monomeric mixture containing N,N-dimethylacrylamide 10% vinylidene chloride and 10% methyl methacrylate.

4. A spinning solution containing from -65% acetone and 15-35% of a mixture containing 70-95% of a cellulose acetate having an acetyl content of 35-41% and 30-5% of an acetone-soluble copolymer prepared by polymerizing a monomeric mixture containing 65% N,N-dimethylacrylamide and 35% methyl acrylate.

References Cited in the file of this patent UNITED STATES PATENTS 2,156,069 Schlack Apr. 25, 1939 2,267,842 Schlack Dec. 30, 1941 2,311,548 Jacobson Feb. 16, 1943 2,404,723 Merner July 23, 1946 2,790,789 Miller Apr. 30, 1957 

1. A SPINNING SOLUTION CONTAINING 85-65% ACETONE, 15-35% BY WEIGHT OF A MIXTURE COMPRISING 70-95% OF A CELLULOSE ACETATE HAVING AN ACETYL CONTENT OF 35-41% AND 30=5% OF AN ACETONE SOLUBLE POLYMER SELECTED FROM THE CLASS CONSISTING OF HOMOPOLYMERS OF N,N-DIMETHYLACRYLAMIDE AND COPOLYMERS OF N,N-DIMETHYLACRYLAMIDE WITH AT LEAST ONE UNSATURATED COMPOUND HAVING THE GROUPING 